IT happened in 2004 when the Veterinary Services Department undertook a study to check on the prevalence of diseases among pigs based on the samples collected during the Nipah outbreak in Peninsular Malaysia in 1999.

When the 1,000 samples went through laboratory tests, it was found that 26.5 per cent showed the presence of influenza H1N1, but no isolation work was done.

Veterinary Services director-general Datuk Dr Abd Aziz Jamaluddin said there might have been outbreaks of the disease but the scale, in terms of mortality and morbidity, might have been very small and they were overlooked by the farmers.

Many of the animals might have also acquired immunity and, thus, did not succumb to the disease.

"We already knew that the virus existed among the pigs, but it is not the same strain that is causing the influenza in humans now," he told the New Straits Times.

He said the department was aware of H1N1 and the H3N2 strain, and the vaccines being used to vaccinate pigs in the United States and Europe, but there was no attempt to bring the vaccines to Malaysia because there was no immediate danger.

In 2006, another study was conducted by the department which also included a researcher from Universiti Putra Malaysia.

This time, they took blood samples and nasal swabs from pigs at random and the result showed the virus still existed.

Dr Abd Aziz said there was evidence of H1N1 and H3N2 circulating in the pig population and believed that its prevalence was 12.2 per cent among the country's pig herds.

He said pigs were permissive to both human and avian influenza viruses and were an intermediate host for the genesis of pandemic influenza viruses.

With the influenza A (H1N1) outbreak among human, the department has given approval for two companies -- Pfizer (Malaysia) Sdn Bhd and Laboratorios Hipra -- to bring in the vaccines for pigs to contain the H1N1 and H3N2.

The vaccines, which are expected to arrive from the US and Europe next week, will be used on pigs under a pilot project to ascertain whether it would help to contain the spread of the disease.

"If successful, we will advise the government on mass vaccination," he said, adding that about 1.7 million pigs in 776 farms would be vaccinated.

Dr Abd Aziz said the main aim was to reduce the risk of the emergence of the virus among humans and also to protect the pigs.

Although the Nipah virus has been eliminated in Malaysia, the department continues to keep watch on pig farms.

On measures taken by the department to deal with a H1N1 outbreak among human, Dr Abd Aziz said all state Veterinary Departments had teams to handle such a situation.

It has also stepped up the level of bio-security at all pig farms, including those in Sabah and Sarawak.

"All those working in pig farms must wear protective attires including gloves and masks.

"Those who are sick have been told to keep away from the farm. That is a regulation which must be adhered to as we do not want the pigs to be infected."

The major pig-rearing states are Penang, Perak, Selangor, Malacca and Johor.

As of Wednesday, the department had checked 341 pig farms and the animals in 22 of them showed the presence of influenza-like symptoms, but not the H1N1 strain.

Dr Abd Aziz said the department hoped to cover all the 776 farms by end of the month.

"We not only look at clinical symptoms but also collect 30 blood samples and nasal swabs from each high risk farms to be sent for laboratory tests at the Veterinary Research Institute. To date, no sample has shown signs of the current strain."

The department plans to reorganise the pig industry to avert major disease outbreak.

He said the government did come out with a blueprint in 1991 to relocate pig farms to one area, but it never materialised in all states due to issues regarding the allocation of land by state governments and protests by some people.

He said Negri Sembilan and Sarawak have designated pig farms while Sabah is looking for a proper site.

Other states which have earmarked designated areas are Perak, Selangor and Johor.

"Since designating a place for pig rearing is a problem, we have moved on to developing modern pig farming, meaning the existing pig farms must upgrade to meet the requirements of the department in order to operate."

The department which runs a 24-hour operations centre has seven regional laboratories besides the Veterinary Research Institute in Ipoh and is proposing for a Centre for Animal Disease Control to be sited in Labu, Negri Sembilan.